$ { \left[\begin{array}{rrr}{-2} & {4} & {2} \\ {4} & {-1} & {-2}\end{array}\right]+\left[\begin{array}{rrr}{4} & {2} & {-1} \\ {-1} & {-2} & {2}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{-2}+{4} & {4}+{2} & {2}+{-1} \\ {4}+{-1} & {-1}+{-2} & {-2}+{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{2} & {6} & {1} \\ {3} & {-3} & {0}\end{array}\right]}$